The growth of the Internet and multi-media applications for digital components such as cell-phones, personal digital assistants (PDAs), computers, and the like has resulted in an ever increasing demand for bandwidth. Along with the growth, the infrastructure needed to handle the increase in bandwidth to support the growth has also increased. Fiber based networks have been deployed to meet the need for the increasing bandwidth demands. Communication networks that are fiber based networks have the capability of making or breaking signal paths depending on the demands of the nodes in the network. Fast switching is therefore needed in order to fully exploit the available bandwidth of the fiber.
Different switching technologies have been developed with the aim of achieving fast and reliable switching. For example, optical micro-electro-mechanical systems (MEMS) switching based on silicon technology, thermal optical switching, electro-optic switching, and acousto-optic switching are the technologies that have been implemented. Drawbacks exist with each type of switch for e.g. MEMS switches and thermo optic switches have switching times of the order of milliseconds, which is slow for a 10 Gb/s LAN communication network, thermo optic switches have a high insertion loss of about 8 dB. Electro-optic switches are considerably faster with switching times in nanoseconds but suffer from high insertion losses of about 9 dB. Acousto-optic switches have switching times in the order of microseconds and an insertion loss of about 6 dB.
Further development of switching technologies is needed to fully use the bandwidth of high-speed fiber networks and other networks.